Supermoon on Saturday evening & Sunday morning:
Look out for a bigger, brighter, Full Moon, this weekend!
The Full Moon on 6 May will happen at the time when the Moon is at its closest to the Earth all year. This means that it will appear particularly big and bright in the sky - up to 30% brighter than some other Full Moons this year. The increase in apparent size won't be quite so noticeable - it will be 14% bigger than some of the other Full Moons this year.
It's all due to the Moon's elliptical orbit around the Earth, which means that its distance from us is constantly varying. Closest approach to Earth is called 'perigee', and due to various other factors, some perigees are closer than others. And it so happens that the closest lunar perigee of 2012 coincides very closely with the Full Moon on May 6. In fact, Full Moon will be at 04.35, and the perigee will be at 04.33, BST. The distance of the Moon then will be 356,955 km, compared with the mean distance of 384,400 km. That's 27,445km closer than average.
Thus the Full Moon will appear noticeably bigger and brighter than usual on May 5 - 6. The effect will probably be most noticeable at moonrise and moonset, because of the so-called Moon Illusion, which makes the Moon appear bigger when it is close to the horizon.
So have a look at Moonrise in the SE on the evening of Saturday 5th at about 8.45 p.m., and if you are up early, at Moonset on Sunday morning at about 05.20 in the SW.